Porsche 928 S 1986 Driver Manual page 57

Tips for winter operation
Engine oil
Change the engine oil and refill with oil of the
correct viscosity before the cold season be-
gins. If you are using multi-grade oil then it is
not necessary to carry out temperature relat-
ed oil changes and you can take advantage of
the extended oil change intervals to the full.
(See also "Filling capacities" and "Engine
Oils".)
Battery
The battery capacity drops with lower tem-
peratures, but the demands made upon the
battery generally increase. Therefore, have
the battery checked and charged, if neces-
sary, in good time. Also have the electrolyte
level checked, and the terminals greased.
See chapter "Battery check and care".
Corrosion protection
The salt spread on winter roads can have a
detrimental effect on your car's bodywork.
You should therefore wash the car as often
as convenient in accordance with our care
instructions. Have a preservative applied
and the underseal checked in an authorized
garage before and after the cold weather
season.
Coolant
The coolant additive provides both antifreeze
protection at low temperatures and corrosion
protection for the engine components which
is especially suited to aluminium parts. There-
fore, the vehicle must never be run without
coolant additive. (Minimum concentration ap-
prox. 30 % providing frost protection of approx.
17°C to 18°C.)
The all-season cooling fluid in the cooling
system, put in by the manufacturer, offers
protection down to -30° C (Scandinavian
countries-40° C).
At the onset of colder weather, have the cool-
ing fluid checked to make sure that the ne-
cessary protection is afforded. When neces-
sary, top up with antifreeze. For amounts see
chapter "Filling capacities".
Brakes
After driving for extended periods on salt
covered roads a film can form on the brake
discs and pads which considerably reduces
friction and thus the braking effect.
The wheel brakes should therefore be cleaned
every two weeks or so with a powerful water
jet. The cleansing effect of automatic washers
is insufficient.
Door and window seals
To prevent the freezing of the rubber seals on
the doors and hood top, they should be treated
with talcum powder or glycerine.
Door locks
To prevent the door locks freezing up, the lock
cylinders should be masked when washing
the vehicle to avoid ingress of water. Should
however the locks still freeze up, a proprietary
de-icing solution can be used to free them. A
warmed-up key can also be useful, but never
use force.
Water reservoirs
To ensure the function of the screen and head-
light washers under frost conditions, anti-
freeze should be added to the water. A mixture
of one part household spirit to three parts
water also works very well.
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